Number as sum of distinct powers of 3 #medium #math


https://leetcode.com/problems/check-if-number-is-a-sum-of-powers-of-three/description/

Arithmetic sum #medium #math


https://leetcode.com/problems/count-total-number-of-colored-cells/description/

https://leetcode.com/problems/find-missing-and-repeated-values/description/


Missing and repeated in 1..n array #medium #math

Min diff primes pair in left..right #medium #math


https://leetcode.com/problems/closest-prime-numbers-in-range/

Min sum of differences of x times #medium #math #quickselect



https://leetcode.com/problems/minimum-operations-to-make-a-uni-value-grid/description/

Sum of all subsets xors #easy #bit #math


https://leetcode.com/problems/sum-of-all-subset-xor-totals/description

https://leetcode.com/problems/count-the-number-of-powerful-integers/description/


Numbers in range start..finish, digits up to limit #hard #dp #math

Count palindromes of length n, divisible by k #hard #math #permutations


https://leetcode.com/problems/find-the-count-of-good-integers/description/

https://leetcode.com/problems/count-good-numbers/description/


Count (0,2,4,6,8)(2,3,5,7) generated strings of length n #medium #math

https://leetcode.com/problems/count-the-number-of-good-subarrays/description/

Subarrays with at least k equal pairs #medium #sliding_window #math

https://leetcode.com/problems/rabbits-in-forest/description


Count total rabbits from other numbers #medium #math #brainteaser

Permutations of even-odd position sums equal #hard #dp #math


https://leetcode.com/problems/count-number-of-balanced-permutations/description/

t steps to convert char into next nums[c] chars #hard #dp #math


https://leetcode.com/problems/total-characters-in-string-after-transformations-ii/description

https://leetcode.com/problems/divisible-and-non-divisible-sums-difference/description/


Sum non-divisible minus sum divisible #easy #math

https://leetcode.com/problems/distribute-candies-among-children-ii/description/


Ways to give limited from n candies to 3 kids #medium #math #combinations

# 17.06.2025
[3405. Count the Number of Arrays with K Matching Adjacent Elements](https://leetcode.com/problems/count-the-number-of-arrays-with-k-matching-adjacent-elements/description/) hard


Combinations k equal siblings 1..m in [n] array #hard #combinatorics #math

# 23.06.2025
[2081. Sum of k-Mirror Numbers](https://leetcode.com/problems/sum-of-k-mirror-numbers/description) hard


n palindromes in both 10 and k-base #hard #math

# 13.08.2025
[326. Power of Three](https://leetcode.com/problems/power-of-three/description) easy


Is n power of 3? #easy #math

# 17.08.2025
[837. New 21 Game](https://leetcode.com/problems/new-21-game/description) medium

Probability sum of random(1..m) less than n when stop adding at k #medium #math #probability

# 18.08.2025
[679. 24 Game](https://leetcode.com/problems/24-game/description) hard

Can a,b,c,d = 24 with ops */+-() #hard #backtracking #math